Fan for heat exchange devices



July 18, 1944; I

D. w. LAKE ETAL FAN FOR HEAT EXCHANGE DEVICES Filed June 29, 1942 3 Sheets-Sheet 1 4M ffor/zeyr 3, 74. 4min 5.5 27 f g m Wm M f A Q July 18, 1944. D. W. LAKE ET AL 2,354,128

FAN FOR HEAT EXCHANGE DEVICES Filed June 29, 1942 5 Sheets-Sheet 2 W Tact iris/fen;

July 18, 1944.

D. w. LAKE .ET AL 2,354,128 FAN FOR HEAT EXCHANGE DEVICES Filed June 29, 1942 3 Sheets-Sheet 3 Patented July 18, 1944 FAN FOR HEAT EXCHANGE! DEVICES Donald W. Lake, Downers Grove, and Jack Briskin, Chicago, Ill., assignors to Excel Auto Radiator Company, Chicago, 111., a corporation of Delaware Application June 29, 1942, Serial No. 448,884

10 Claims.

The present invention relates to heat exchange devices and is particularly directed to devices of this character which are used as heaters for heating air and circulating the same in automotive vehicles such for example as the usual passenger automobile. It is the principal purpose of the present invention to provide a novel mechanism whereby a more efficient and simple utilization of the heating element and its air circulating device may be had.

More particularly, it is a purpose of the present invention to provide a novel construction wherein air is propelled in both directions through the heating element by a single rotating fan of novel construction. The invention contemplates a con- 1 struction wherein a fan is located immediately in back of the heater element, this fan being constructed of a single sheet of metal having propeller blades adapted to force air forwardly through the heating element and having paddle members projecting rearwardly from the propeller blades and surrounding the drive motor, these paddle wheels being in turn enclosed in an annular casing having an outlet through which air may be delivered to a suitable duct for use in defrosting the windshield or in supplying air to a remote portion of the passenger compartment.

The invention contemplates a novel fan construction wherein both the propeller and the paddle wheel arrangements are balanced and whereby the metal sheet from which the fan is made is utilized with a minimum amount of waste.

The features and advantages of the invention will appear more fully as the description proceeds, reference being had to the accompanying drawings wherein a preferred form of the invention is shown. It should be understood however that the drawings and description are illustrative only and are not to be taken as limiting the invention except insofar as it is limited by the claims.

In the drawings:

Fig. 1 is a view partly in section and partly in side elevation of a heat exchange device embodying our invention;

Fig. 2 is a plan view partly in section of the heat exchange device;

vFig. 3 is a fragmentaryright-hand elevational view taken on the line 3-3 of Fig. 1;

Fig. 4 is a sectional view taken on the line 4-4 of Fig. 1; and

Fig. 5 is a fragmentary sectional view taken on the line 5-5 of Fig. 1.

Referring now in detail to the drawings, the present invention is embodied in a heat exchange device of the type usually employed in heating the interior of automobiles. Such heat exchange devices comprise a hot water unit embodying oppositely disposed headers l0 and H, each header being connected to a water circulating pipe, the pipe to the header l0 being shown at l2 and the pipe to the header being shown at [3. The headers ill and H are connected by a plurality of tubes l4 (see Figs. 1 and 2), these tubes being flattened in cross section and being arranged in a plurality of rows as illustrated in Fig. 1, the rows being staggered whereby to obtain adequate contact with the air that flowspast the tubes in the direction indicated by the arrows in Fig. l. The tubes have mounted thereon spaced radiating fins which are heated by contact with the tubes so as to further communicate heat to the air flowing between the fins and the tubes. The heater element just described is enclosed in a heater front I6 having a multiplicity of louvers such as H hinged at the front thereof, these louvers being adjustable to limit and direct the air flow in a manner well known in the art.

The heater front has a back plate secured thereto, there being suitable posts l8 mounted in the heater front to receive screws I9 to clamp the back plate l1 in place.

The back plate has an annular cone-shaped, rearwardly extending flange which is adapted to receive a motor and fan housing 2 I. The motor and fan housing 2| is a pan shaped metallicv housing flared outwardly from its base 22 to its open end where it engages with the flange 20. A partition 23 is provided in the housing 2| about half way between the base 22 and the open end. This partition comprises an annular channel shaped strip which is fastened in place in the housing 2| in any suitable manner, such as by spot welding. Toward the open end of the housing 2| from the partition the housing is provided with a multiplicity of relatively large openings 24 to permit air to flow into the housing and to the heater unit. A ring 25 is mounted by soldering or otherwise to the fins I5, this ring being utilized to segregate the air flowing into the heater unit from the rear from the air flowing to the rear through the heater unit.

Within the housing 2| there is mounted a drive motor 26 which has a shaft 21 to support and rotate a fan member 28. The motor itself is extended through an opening 29 in the base 22 of the housing 2| and is provided with a mounting plate 30. The mounting plate 30' is in turn fastened by two bolts 3| and 32 to a mounting bracket 33 which is substantially U-shaped. The

bracket 33 is fastened to the back plate I! and is provided with apertures 34 and 35 by which it may be secured to the dashboard or other mounting for the heater unit. The rear portion of the bracket 33 is provided with side flanges 36 and 37 for the purpose of strengthening the bracket, these side flanges extending forwardly along the legs of the bracket as indicated in Fig. 2. The bracket also has mounted thereon two plates 38 and 39 (see Fig. 3) which plates serve as supports for the pipes l2 and [3. It will be noted that the bracket has bosses 40 and 4! receiving nuts 42 and 43 for the bolts SI and 32 which clamp the mounting plate 30to the bracket. Spacers 44 and 45 are employed to properly space the mounting plate with respect to the bracket.

Referring now to the fan member 33, this fan member comprises a hub portion 46 and three propeller blades 41, 48 and 49 equally spaced around the axis of the hub. The blades are struck up from a single sheet of metal and between the blades there are radially and rearwardly extending arms 50, and 52, these arms terminating in paddles 53, 54 and 55. The material of the paddles as well as of the arms is a part of the fan sheet from which the propeller blades are made, the paddles and the propeller blades being blanked out from the fan sheet so that a minimum loss of material is incurred. The several paddles each comprises an inwardly extending blade portion 56 and an outwardly extending blade portion 51. The blade portions 56 are at the forward or leading edge of the paddles, while the blade portions 51 are at the trailing edges of the paddles. The inwardly extending portions 56 extend inwardly in close proximity to the periphery of the motor 26 itself. At the ends of the paddles 53, 54 and 55, remote from the hub 46, the paddles are connected by a ring 58 which is soldered or welded to the paddles to give rigidity to the structure. The housing 2| is so shaped about the paddles as to provide a chamber which gradually increases in cross sectional area from a point 59 to a point 60 thus forming an expanding channel in which air driven in the direction of the arrows shown in Fig. 5 by the paddles will be carried along and discharged through an outlet opening 6! of the housing 2|. The particular paddle construction employed is advantageous in that it provides for the air being circulated first receiving impetus from the inner portions 56 and then receiving impetus from the portions 5'? which are spaced rearwardly from the portions 56. It has been found by actual use that afan unit constructed in this fashion is highly efiicient in comparison with the well known blower fans and propeller fans combined, and that a much smaller power consumption is necessary for adequate supply of air.

Air is of course drawn into the vicinity of the inner paddles due to the creation of a partial vacuum there, and this air is drawn through the center or dead portion of the propeller fan which comprises the three propeller blades 41, G8 and 49. It is well known that propeller fans at the mid or hub portion are not effective. This air that is drawn in passes through the portion of the heater unit definedby the ring and in order to facilitate its entry the propeller blades are deformed within the area defined by the ring 25 as indicated at 62, 63,and 64 on their trailing edges and at 65, 66 and 6'! on their leading edges. The dethe points 65, 66 and 6'! toward the heater out of the plane of the blade so that they will act to force the air rearwardly. The deformation at the trailing edges is away from the heater so as to permit ready flow of the air through the central portion of the fan and to the paddles.

It is found necessary in order to obtain an adequate supply of air to make the openings 24 quite large since they must supply sufficient air to cover the greater portion of the heater area. The efficiency of air transfer is lost if these openings are made to restrict it. In actual practice therefore the openings are made even larger than shown in the drawings.

From the foregoing description it is believed that the construction and operation of the device embodying our invention will be readily apparent to those skilled in this art.

We claim:

1. In a fan structure for a heat exchange device, the combination of a propeller fan member formed of sheet metal comprising a plurality of obliquely positioned blades formed integrally with each other and extending radially in spaced relation adapted upon rotation of the fan member to drive a stream of air axially therefrom, arms formed integrally with said radially positioned blades between each two adjacent blades and extending rearwardly from said blades, and paddles on said arms formed integrally with the arms in position to force air outwardly by centrifugal action upon rotation of said fan member.

2. In a fan structure, the combination of a propeller fan member, means for rotating said fan member for driving a stream of air axially, arms extending rearwardly from the fan member, and paddle means on each of said arms each comprising a portion extending inwardly and a portion extending outwardly in offset relation to said inwardly extending portion.

3. In a fan structure, the combination of a propeller fan member, means for rotating said fan formation comprises, bending the leading edges at member for driving a stream of air axially, arms extending rearwardly from the fan member, and paddle means on each of said-arms each comprising a portion extending inwardly at the leading edge of said arm and a portion extending outwardl at the trailing edge of said arm.

4. In a fan structure, the combination of a propeller fan member formed from a sheet of metal and comprising a plurality of blades formed integrally with each other and extending radially in spaced relation to each other, means for rotating said fan member for driving a stream of air axially, arms formed integrally with said blades in the spaces between the blades and extending rearwardly from the fan member, and paddle means on each of said arms each comprising 'a panel portion bent inwardly from the leading edge of said arm and a second panel portion bent outwardly from the trailing edge of said arm.

5. In a fan structure, the combination of a propeller fan member formed from a sheet of metal and comprising a plurality of blades formed integrally with each other and extending radially in spaced relation to each other, means for rotating said fan member for driving a stream of air axially, arm formed integrally with said blades in the spaces between the blades and extending outwardly and rearwardly from the fan member, radially extending paddle means on each of said arms comprising panels bent in opposite directions at opposite edges of the arms, and means connecting the outer end portions of said arms rigidly together for holding said paddles in fixed relationship to each other.

6. In a fan structure, the combination of a propeller fan member formed from a sheet of metal and comprising a plurality of blades formed integrally with each other, means for rotating said fan member for driving a stream of air axially, arms formed integrally with said blades in the spaces between the blades and extending outwardly and rearwardly from the fan member, radially extending paddle means on each of said arms comprising panels bent in opposite directions at opposite edges of the arms, and housing means about said paddles arranged to carry away a stream of air forced outwardly by said paddles upon the rotation of said fan member.

7. In a fan structure for a heat exchange device, the combination of a central mounting portion, a plurality of obliquely positioned propeller blades projecting radially from said portion and being spaced apart at their junction with said portion, said blades being adapted upon rotation to drive a stream of air axially forward from the fan structure, arms fixed to said mounting portion in the spaces between the propeller blades, said arms extending rearwardly from the mounting portion and having paddles thereon at a distance from the mountin portion, said paddles being arranged to force air outwardly by centrifugal action upon rotation of the fan structure.

8. In a fan structure for a heat exchange device, the combination of a central mountin por tion, a plurality of obliquely positioned propeller blades projecting radially from said portion and being spaced apart at their junction with said portion, said blades being adapted upon rotation to drive a stream of air axially forward from the fan structure, arms fixed to said mounting portion in the spaces between the propeller blades, said arms extending rearwardly from the mounting portion and having paddles thereon at a distance from the mounting portion, said paddles being arranged to force air outwardly by centrifugal action upon rotation of the fan structure, and rigid connections between the free ends of said arms.

9. In a fan structure for a heat exchange device, the combination of a central mounting portion, a plurality of obliquely positioned propeller blades projecting radially from said portion and being spaced apart at their junction with said portion, said blades being adapted upon rotation to drive a stream of air axially forward from the fan structure, arms fixed to said mounting portion in the spaces between the propeller blades, said arms extending rearwardly from the mounting portion and having paddles thereon at a distance from the mounting portion, said paddles being arranged to force air outwardly by centrifugal action upon rotation of the fan structure, and a housing about said blades and paddles, said housing having air openings outwardly of the blade ends, a discharge spout outwardly of the paddles, and a partition extending radially inward between the blades and paddles, the end of the housing forwardly of the propeller blades being open.

10. In a fan structure for a heat exchange device, the combination of a central mounting portion, a plurality of obliquely positioned propeller blades projecting radially from said portion and being spaced apart at their junction with said portion, said blades being adapted upon rotation to drive a stream of air axially forward from the fan structure, arms fixed to said mounting portion in the spaces between the propeller blades, said arms extending rearwardly from the mounting portion and having paddles thereon at a distance from the mounting portion, said paddles being arranged to force air outwardly by centrifugal action upon rotation of the fan structure, and said propeller blades having their edge portions immediately adjacent the central mounting portion bent to direct air rearwardly toward the paddles as the fan structure is rotated.

DONALD W. LAKE. JACK BRISKIN. 

